The invention relates to an arrangement for equalizing the attenuation versus frequency curve of a signal carrier transmission system within a predetermined frequency range.
It is already known to equalize the attenuation versus frequency curves of transmission systems utilizing equalizers based upon the echo principle, the cosine principle and utilizing equalizers having attenuation versus frequency curves exhibiting adjustable-amplitude attenuation bumps (elevations and depressions). Such equalizers are capable of equalizing the attenuation versus frequency curve of signal carrier transmission systems exhibiting unpredictable frequency distortion, to the extent that the equalizers have a resolving power sufficiently great for the details of the attenuation versus frequency curves. This type of equalizer is referred to herein as a universal equalizer. The universality of such an equalizer is attributable to the type of theoretical considerations associated with the particular equalizer type: the use of Fourier analysis in the case of echo equalizers, the use of the sampling theorem in the case of adjustable-bump equalizers.
Federal Republic of Germany Pat. No. 1,805,461 discloses an equalizer into whose attenuation versus frequency curve there can be introduced a plurality of attenuation curve bumps of adjustable magnitude and lateral position (relative to the frequency axis) by utilizing adjusting components. However, that patent contains no information concerning the use of such equalizers as universal equalizers.
It is a general object of the invention to provide a universal equalizer arrangement, for equalizing the attenuation versus frequency curves of signal carrier transmission systems, of a novel design such as to inherently be considerably less expensive than comparable equalizers of the prior art.